Iran Primer: Timeline of Iran's Nuclear Activities

by SEMIRA NIKOU

The United States and Iran signed a civil nuclear cooperation agreement as part of the United States Atoms for Peace program. The agreement provided for U.S. technical assistance and the lease of enriched uranium to Iran. It also called for research cooperation on peaceful nuclear energy uses.

1967

November The Tehran Nuclear Research Center, supplied by the United States, opened. It was equipped with a 5-megawatt nuclear research reactor called the Tehran Research Reactor (TRR), fueled by highly enriched uranium.

1968

July 1 Iran signed the Nuclear Non-Proliferation Treaty (NPT). Parliament ratified it in February 1970. Uranium enrichment was allowed under the treaty.

1974

May 15 Iran signed the NPT's Safeguards Agreement with the International Atomic Energy Agency (IAEA). The safeguards allowed inspections for the purpose of verifying that nuclear enrichment for peaceful nuclear energy is not diverted to nuclear weapons or other nuclear explosive devices.

November West German company Kraftwerk Union, a subsidiary of Siemens, agreed to construct two 1,200-megawatt light water reactors to produce nuclear energy at Bushehr. Construction began in August 1975, but the formal contract was not signed until mid-1976.

1975

The Ford administration expressed support in principle for the shah's plan to develop a full-fledged nuclear power program to diversify Iran's energy sources. The shah wanted the capacity to generate 23,000 megawatts of electricity with the ability to reprocess U.S.-supplied fuel.

1976

April 20 President Gerald Ford issued National Security Decision Memorandum 324 supporting the shah's ambitions and helping Iran formulate a plan to build 23 nuclear power reactors. But the administration refused to allow Iran to have the independent reprocessing capabilities sought by the shah. Ford's memorandum instead approved a multinational reprocessing plant in Iran that would also enable the United States to participate in the project. Iran rejected the multinational option and pushed for a comprehensive national nuclear program.

1977

August President Carter reopened negotiations on the shah's quest for a nuclear energy program.

1978

January Iran and the United States initialed a nuclear agreement in which Iran agreed to safeguards beyond NPT requirements. In return, the United States granted Iran "most favored nation" status for reprocessing so that Iran would not be discriminated against when seeking permission to reprocess U.S.-supplied fuel.

1979

After the 1979 revolution, the United States stopped supplying highly enriched uranium for the Tehran Research Reactor.

July 31 Kraftwerk Union terminated work on the Bushehr reactor when Iran failed to make payments.

1984

February German engineers returned to Iran to do a feasibility study to complete the Bushehr reactor.

March 24 Iraq's attack on the Bushehr nuclear power plant did serious damage.

December Iran opened a nuclear research center at Isfahan with China's assistance. In 1985, China supplied the center with a "training reactor."

1987

May 5 After 18 months of negotiations, Argentina concluded a $5.5 million deal with Tehran to supply a new core for the Tehran Research Reactor so it would operate with only 20 percent enriched uranium, instead of the previous 90 percent. In 1989, Argentina replaced the core. In 1993, Argentina delivered around 50 pounds of 20 percent enriched uranium to fuel the reactor.

Aug. 25 Russia and Iran signed a cooperation agreement on the civil use of nuclear energy, including construction of a nuclear power plant.

1995

January Iran signed a contract with the Russian Ministry of Atomic Energy to build a light water reactor at Bushehr under IAEA safeguards. Russia was under a contractual obligation to complete the plant within 55 months. The project's completion was delayed until August 2010.

1997

May The IAEA expanded the Safeguards Agreement by adopting the Additional Protocol. Under the latter, inspectors would be allowed to conduct short notice inspections and be provided with multiple entry/exit visas. Iran signed the Additional Protocol in 2003, but had not ratified it as of 2010.

1998

Feb. 23 The Clinton administration opposed Iran's nuclear energy program on grounds that Iran had sufficient oil and gas reserves for power and that work on the nuclear power reactor could indirectly contribute to a weapons program.

March 6 Under U.S. pressure, Ukraine announced that it would not sell two turbines for use at the Bushehr reactor.

1999

May 7 Russia said Iran wanted to expand nuclear cooperation, potentially including the building of a second nuclear power plant.

May 19 President Mohammad Khatami paid a five-day state visit to Saudi Arabia, where Iran and Saudi Arabia issued a joint statement expressing support for turning the Middle East into a zone free of weapons of mass destruction. They said Israel's production and stockpiling of nuclear weapons, along with its non-compliance with international laws and treaties, posed a serious threat to peace and security in the region.

2000

March 14 President Clinton signed the Iran Nonproliferation Act, which allowed the United States to sanction individuals and organizations providing material aid to Iran's nuclear, chemical, biological and ballistic missile weapons programs.

2001

March 12-15 Russian President Vladimir Putin and Iranian President Khatami signed nuclear and military cooperation accords. Khatami said Iran wanted a second nuclear power plant after the completion of Bushehr.

2002

Jan. 8 Former President Akbar Hashemi Rafsanjani said, "Iran is not seeking to arm itself with non-conventional weapons."

Aug. 15 The National Council of Resistance of Iran, an exiled opposition group, revealed that Iran was building two secret nuclear sites - a uranium enrichment plant and research lab at Natanz and a heavy water production plant in Arak. President Khatami acknowledged the existence of Natanz and other facilities on Iran's state-run television and invited the International Atomic Energy Agency to visit them.

Sept. 1 Russian technicians began to assemble heavy equipment in the Bushehr reactor, despite U.S. attempts to convince the Russians not to participate. But the plant faced frequent delays in construction.

2003

Feb. 9 President Khatami said Iran had discovered and extracted uranium in the Savand area. He cited Iran's "legitimate right to obtain nuclear energy for peaceful aims" and expressed readiness to accept international inspections of its nuclear activities.

May 6 Iran's Atomic Energy Organization presented the United Nations with a sketch of Iran's nuclear program, insisting that the program was peaceful.

May 17 Tehran backed a proposal by Syria to rid the Middle East of weapons of mass destruction.

June 19 An IAEA report did not find Iran in violation of the NPT but said Iran should have been more forthcoming about the Natanz uranium enrichment facility and the Arak heavy water production plant. The U.N. watchdog agency later urged Iran to sign and ratify the Additional Protocol to the Safeguards Agreement of the Nuclear Non-Proliferation Treaty, which would allow inspectors more access to nuclear sites and the right to sudden inspections.

Aug. 26 IAEA inspectors found traces of highly enriched uranium at Iran's Natanz nuclear plant. Iran claimed the traces came from equipment imported from another country.

Sept. 19 President Khatami said, "We don't need atomic bombs, and based on our religious teaching, we will not pursue them...but at the same time, we want to be strong, and being strong means having knowledge and technology."

Sept. 25 U.N. weapons inspectors found traces of highly enriched weapons-grade uranium at a second site near the capital city of Tehran. The IAEA set a deadline of Oct. 31 for Iran to prove it was not making nuclear weapons.

Oct. 21 In talks with Britain, France and Germany (EU-3), Iran agreed to suspend uranium enrichment and processing activities and to open nuclear sites to unannounced inspections by the U.N. watchdog agency. It also agreed to sign the Additional Protocols of the Non-Proliferation Treaty and its safeguards agreement with the IAEA.

Oct. 24 1,500 Iranian protestors gathered in Tehran to denounce the recently concluded agreement between Tehran and the EU-3.

Nov. 12 The IAEA concluded there was no evidence of a secret nuclear weapons program in Iran but showed concern about its production of plutonium. President Khatami said that the plutonium was used for manufacturing pharmaceuticals and the small amount produced by Iran could not make a nuclear bomb.

Dec. 18 Tehran signed the Additional Protocol to the Non-Proliferation Treaty's Safeguards Agreement. The Additional Protocol granted IAEA inspectors greater authority in their nuclear verification programs. Since then, Iran has at times voluntarily allowed more intrusive inspections, but the Iranian parliament has not yet ratified the Additional Protocol.

2004

Feb. 22 Iran acknowledged having secretly bought nuclear parts from international sources, although Tehran continued to insist that its goal was electricity production and not nuclear weapons.

Apr. 7 Iran declared its plans to construct a heavy water reactor to produce radioisotopes for medical research. Western envoys warned that the facility could reprocess the spent fuel rods to produce plutonium.

Aug. 28 President Khatami said Iran had a right to enrich uranium and was willing to provide guarantees to the IAEA that it was not developing nuclear weapons.

Oct. 6 Tehran announced that it had produced tons of the hexafluoride gas needed to enrich uranium by converting a few tons of yellowcake uranium.

Nov. 14 In negotiations with Britain, France and Germany, Iran accepted the Paris accord, which recognized Tehran's rights to pursue nuclear technology for peaceful purposes and reaffirmed Iran's commitment not to acquire nuclear weapons. In exchange, Iran voluntarily agreed to temporarily suspend uranium enrichment activities and allow the IAEA to monitor the suspension.

Nov. 15 The IAEA reported that it had not found any evidence that Iran had tried to develop nuclear weapons, although it could not rule out the existence of nuclear materials that had not been declared.

Nov. 22 Iran invited the IAEA to monitor the suspension of all enrichment-related activities.

Nov. 30 Iran said that it had not abandoned its right to enrich uranium and that the suspension was only temporary. European officials hoped to make the suspension permanent in return for trade deals and other incentives.

Dec. 22 Iran's intelligence minister announced the arrest of more than 10 people on spying charges. Tehran charged the spies were passing sensitive information on Iran's nuclear program to the Israeli Mossad and the CIA.

2005

Jan. 13 IAEA inspectors were only allowed partial access to the Parchin military base near Tehran. Under the NPT, Iran was not required to allow inspectors into its military bases. But the Bush administration consistently expressed concern that Iran's failure to allow full access to its suspected military bases and facilities was linked to a secret nuclear weapons program.

Jan. 17 President Bush said military action against Iran remained an option, "if it continues to stonewall the international community about the existence of its nuclear weapons program."

Feb. 7 Iran's Minister of Defense Ali Shamkhani said in an interview that it was not in Iran's national interest to acquire nuclear weapons.

Feb. 28 Tehran and Moscow signed an agreement that stipulated that Russia would supply nuclear fuel for the Bushehr facility and that Iran would return all spent fuel rods to Russia to ensure the fuel was not diverted for other use.

May 15 Iran's parliament approved a non-binding resolution urging the government to resume uranium enrichment for peaceful use.

Aug. 1 Iran informed the IAEA that it had decided to resume activities at the Isfahan uranium conversion center. The U.N. nuclear watchdog agency urged Iran not to take any action that would prejudice negotiations with Britain, France and Germany (the EU-3) or undermine the IAEA inspection process.

Aug. 5 Britain, France and Germany (the EU-3) proposed the "Framework for a Long-term Agreement" to Iran. The deal offered assistance in developing peaceful nuclear energy in exchange for a binding commitment that Iran would not to pursue fuel cycle activities other than for light water power and research reactors. It also called for a halt on construction of a heavy water research reactor at Arak. Iran rejected the proposal, as it required Tehran to abandon all nuclear fuel work.

Aug. 8 Iran resumed uranium conversion at the Isfahan facility under surveillance of the IAEA.

Sept. 24 The IAEA found Iran in noncompliance with the NPT Safeguards Agreement and decided to refer Tehran to the U.N. Security Council for further action. The decision followed Iran's repeated failure to fully report its nuclear activities. Tehran countered that it might suspend its voluntary implementation of the Additional Protocol that allowed more intrusive and sudden inspections.

Nov. 20 Iran's parliament approved a bill requiring the government to stop voluntary implementation of the Safeguards Agreement's separate Additional Protocol, which allowed more intrusive and surprise inspections, if Iran were referred to the Security Council. The parliament did not move to block normal inspections required under the Safeguards Agreement, which had been ratified by parliament in 1974.

2006

January Iran broke open internationally monitored seals on the Natanz enrichment facility and at two related storage and testing locations, which cleared the way to resume nuclear fuel research under IAEA supervision.

Feb. 4 The IAEA voted to report Iran to the U.N. Security Council for its non-compliance with its NPT Safeguards Agreement obligations.

July 31 The U.N. Security Council passed Resolution 1696 demanding that Iran suspend its uranium enrichment activities within one month. No sanctions were imposed but the resolution warned that "appropriate measures" would be taken in the case of Iranian non-compliance. Tehran called the resolution illegal.

Aug. 26 Iran's President Mahmoud Ahmadinejad inaugurated a heavy water production plant at Arak. The United States expressed concern that the heavy water would be used in the heavy water reactor at Arak to produce plutonium, an ingredient in making nuclear weapons.

Oct. 2 President Bush signed into law the Iran Freedom Support Act, which imposed economic sanctions on nations and companies that aided Iran's nuclear program.

Dec. 23 The U.N. Security Council adopted Resolution 1737, sanctioning Iran for its failure to comply with Resolution 1696 and halt uranium enrichment. The resolution banned the sale of nuclear-related technology to Iran and froze the assets of key individuals and companies related to the nuclear program.

2007

March 24 The U.N. Security Council adopted Resolution 1747, which banned the sale of arms to Iran increased the freeze on assets.

Dec. 4 A U.S. National Intelligence Estimate on Iran's nuclear activities said there was evidence that Tehran halted its nuclear weapons program in 2003. It assessed with "moderate confidence" that Iran had not re-started its nuclear weapons program as of mid-2007. The findings contradicted the 2005 U.S. intelligence assessment that Tehran was seeking nuclear weapons capability.

2008

Feb. 22 An IAEA report concluded that Iran had not fully answered the international community's questions about its nuclear program and testing of new centrifuge technology for faster uranium enrichment. The report was based in part on intelligence acquired by the Bush administration that allegedly pointed to Iranian efforts to weaponize nuclear materials. The data was extracted from a laptop reportedly smuggled out of Iran in 2004.

March 3 The U.N. Security Council approved Resolution 1803, imposing further economic sanctions on Iran.

July 18 The Bush administration agreed to send U.S. Undersecretary of State William Burns to Geneva to participate with his European counterparts in talks with Iran about its nuclear program. But Iran again rejected the suspension or freeze of its enrichment activities.

Sept. 26 The U.N. Security Council passed Resolution 1835 which reaffirmed three earlier rounds of sanctions against Iran. No new sanctions were imposed, largely because of objections by Russia and China.

2009

Sept. 25 President Obama, French President Sarkozy and British Prime Minister Brown told a press conference that Iran had a covert fuel enrichment plant near Qom. Iran said it had already confirmed the construction of a new pilot enrichment plant to the IAEA in a letter four days earlier. Critics said Tehran disclosed the site once it discovered the facility was already under surveillance.

Oct. 1 Iran met in Geneva with permanent members of the U.N. Security Council and Germany to discuss Iran's nuclear program. The parties outlined a proposal for Iran to ship 80 percent of its stockpile of low-enriched uranium from Natanz to Russia. The shipment would then go to France for further enrichment and fabrication of fuel rods for the Tehran Research Reactor, which produced isotopes for medical use.

Oct. 19-21 The early October talks in Geneva were continued in Vienna with the presence of the IAEA, on the transfer of Iran's low-enriched uranium. A consensus was reached on a draft agreement. The United States, France and Russia approved the agreement, but Iran backed down due to domestic opposition.

2010

Feb. 12 President Ahmadinejad announced that Iran had produced 20 percent enriched uranium, up from 3.5 percent, in a move that marked a major increase in its capabilities. He said Iran had the capability to enrich the fuel even further.

May 17 Turkey, Brazil and Iran agreed to a nuclear deal similar to the agreement outlined in Geneva in 2009. The proposal called for the transfer of 1,200 kg of low-enriched uranium (3.5 percent) to Turkey, in exchange for 120 kg of 20 percent enriched uranium needed to run the Tehran Research Reactor. The United States and Europeans rejected the deal because Iran had increased its uranium stockpile. The 1,200 kg then represented only about half of Iran's stockpile, rather than the 80 percent it had in the October 2009 deal. Washington also believed the move was a delaying tactic to avert sanctions.

June 9 The U.N. Security Council adopted Resolution 1929, imposing a fourth round of sanctions on Iran. They included tighter financial measures and an expanded arms embargo. President Ahmadinejad said the sanctions were a "used handkerchief that should be thrown in the dustbin," and that they were "not capable of harming Iranians."

June 24 Congress approved the Comprehensive Iran Sanctions, Accountability, and Divestment Act of 2010. It passed unanimously in the Senate and overwhelmingly in the House. The bill expanded existing U.S. sanctions on Iran. It imposed extensive sanctions on foreign companies that export refined petroleum to Iran or invest in Iran's energy sector. The legislation went well beyond U.N. Resolution 1929.

July 6 Iran announced that talks with U.N. Security Council and Germany could begin in September.

July 11 Iran announced it had produced 20 kilograms of 20 percent enriched uranium and had begun work on fuel plates. The fuel was to be delivered to the Tehran Research Reactor by September 2011, for creating medical isotopes. Western powers have repeatedly expressed fear that Iran's capability to enrich 20 percent would help it produce nuclear weapon material, which is around 90 percent.

July 26 The European Union passed sanctions, which banned technical assistance to Iran's oil and gas industry.

Aug. 13 The Russian Federal Atomic Energy Agency (Rosatom) announced that the first reactor at the Bushehr would soon be loaded with nuclear fuel and become Iran's first operational nuclear power plant.

Aug. 21 An official launch ceremony was held to mark completion of the Bushehr reactor, after years of delays. Iran began loading the plant with fuel, in hopes of making it fully operational within a few months. As part of the deal, Russia supplied the reactor with fuel and Iran is required to send back the spent fuel to Russia.

Semira Nikou is a research assistant at the U.S. Institute of Peace. This article is presented by Tehran Bureau, the U.S. Institute of Peace, and the Woodrow Wilson International Center for Scholars as part of the Iran project at iranprimer.usip.org.